JPS59205212A - Cutting device for internal surface of spherical shell - Google Patents

Abstract

PURPOSE:To permit the internal surface of a shell to be high accurately machined under its complete spherical condition, by disassemblably arranging an arm part, to which a tool is mounted, and its guide post so that they can be carried into and out of a shell from its opening part, in the case of a cutting device for the internal surface of the pressureproof shell used in an abyssal research vessel or the like. CONSTITUTION:An arm part 5, holding a cutting tool 6 and being supported to a post 2 fixed by its both end parts in a spherical shell 1 through fixed parts 3, can be slided in an axial direction of the post 2, turned around its axis through a supporting frame 4 and moved in the axial direction of an arm itself, and the arm part provides in its point end a driving gear of the cutting tool. Each member as described in the above can be carried from an opening part 7 such as a hatch and assembled in the spherical shell 1 under its completed condition. In such way, an internal surface of the spherical shell 1 can be high accurately cut by a control unit 9 under the complete spherical condition and finished into a complete true spherical surface by changing a fixed position of the post 2 to the internal surface of the spherical shell, thus never causing any conventional trouble of welding strain or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for cutting the inner surface of a spherical shell that requires extremely high sphericity, such as a pressure-resistant shell of a deep-sea research vessel.

Since external pressure depending on the diving depth acts on the pressure shell of a deep-sea diving research vessel, the pressure shell l is generally made as a spherical shell that is resistant to external pressure, as shown in FIG. If the aM depth of a diving research vessel is, for example, 6,000 m, the external pressure acting on this pressure shell IK reaches approximately 600 Kg/crl VC, and in order to withstand such a large external pressure, pressure shell 1 must have extremely high sphericity. is required. Naturally, there is a hatch la on the top of the pressure shell I for the entry and exit of the operator and equipment, and of course the hatch lid is closed during n1 diving to maintain watertightness, and the spherical shell body l is To ensure that stress is transmitted continuously,
The pressure-resistant shell maintains its true spherical shape even under high external pressure.

Conventionally, cutting of this type of highly accurate spherical shell involves cutting two hemispherical shells that are divided at the equatorial plane using a general-purpose large cutting machine, finishing the hemispherical shell with high precision, and then cutting the two hemispherical shells at the equator. It was welded together to make it a complete sphere, and the welded part was re-cut to finish it off. However, with this method, it was extremely difficult to produce a spherical shell with high sphericity due to distortions caused by assembly and welding of the hemispherical shells and distortions caused by post-heat treatment due to the effects of welding heat. In particular, with the prior art, it has been impossible to cut the inner surface of a spherical shell in a completely spherical state except in a very limited range.

In view of the above-mentioned drawbacks of the conventional cutting method in which a hemispherical shell is cut and then butt welded to form a full spherical shell, the present invention provides an apparatus that can precisely cut the inner surface of a spherical shell in a full spherical state. The purpose is to

The purpose of this is to provide a tool for cutting the inner surface of the spherical shell, an arm to which this tool can be attached and brought to any desired position on the inner surface of the spherical shell, and a support that can be fixed to the inner surface of the spherical shell to guide this arm in the completed state. It has a structure that can be disassembled and assembled so that it can be carried in and out through an opening such as a hatch provided in the spherical shell, and the movement of the arm and the cutting movement of the cutting tool are controlled by a control unit provided outside the spherical shell. This is achieved by

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

FIG. 2 is a diagram showing an embodiment of the present invention, and shows a state in which the main body of the cutting device is assembled and installed in the spherical shell 1 whose inner surface is to be cut. A column 2 supporting an arm 5 that supports a cutting tool 6 at its tip is fixed via a fixing part 3 at both ends of a certain diameter inside a spherical shell. The arm portion 5 is attached to the support column 2 via the support frame 4 so that the support column can move in the axial direction, rotate around the axis, and move in a direction perpendicular to the axis, that is, in the axial direction of the arm itself. The tip of the arm 5 [is, for example, a milling cutter,
A cutting tool such as a grinder and its driving device are installed. Each of the above-mentioned members can be divided into sizes that can be carried into the spherical shell I through an opening 7 that becomes a hatch etc. in the completed state of the spherical shell I, and has a structure that allows them to be assembled within the spherical shell I. It has become. The fixed part 3 of the column 2 is a spherical shell that completely absorbs cutting reaction force! For example, by fitting the support into the inner surface of the spherical shell, fixing it with screws, or bracing the support, so that the support can be transmitted to Fixed. Furthermore, the number of support frames 4 and arm portions 5 is not limited to one set, and a plurality of sets may be provided on one support 2.

The spherical shell l is held by the holding frame 8, but since the cutting reaction force by the cutting tool 6 is received by the spherical shell l via the aforementioned fixed part 3 of the support column 2, the holding frame 8 simply holds the spherical shell. It only needs to have the function of holding it in a predetermined position, and it can be extremely simple. In addition, when the method of fixing the column 2 is to push the column against the inner surface of the spherical shell, the column 2 is held in the holding frame 8 by the outer surface of the part where the fixing part 3 contacts the end of the column 2, and the hydraulic pressure is applied. It is necessary to prevent deformation of the spherical shell by applying a restraining force against the tensile force using a ring or the like.

The axial and radial movement of the arm 5 relative to the column 2 and the rotation around the axis as well as the drive of the cutting tool 6 are controlled by a control unit 9 provided outside the spherical shell I using a control cable passing through the opening 7. Controlled via io'l.

Since this device is constructed as described above, cutting of the inner surface of the spherical shell can be performed with higher precision in the entire sphere. By changing the fixing position of the strut 2 to the inner surface of the spherical shell and performing the cutting process, the inner surface of the spherical shell can be completely machined, making it possible to finish a completely spherical surface in a completely spherical state. It is possible to avoid problems such as welding distortion caused by welding two welds against each other.

In addition, the cutting tool 6 can rotate around the axis of the support column 2.
Since it is possible to move in the axial direction along the column 2 and in the radial direction with respect to the axis, by appropriately combining and controlling the movements of the pillars 2 and 2, it is possible to move not only on the spherical surface but also on local unevenness. Various elegant effects can be obtained, such as making it possible to cut the inner surface in a way that makes it look as if the material has a surface.

In addition, in the above example, the support to which the cutting device is attached is a single straight rod, and both ends of the support are fixed to the inner surface of the spherical shell, but the shape of the support is not necessarily a single straight rod. It is not necessary to have one, and various modifications can be made according to the circumstances of the workpiece, such as the position of the hatch, such as configuring one support 12 fixed on the tripod-like leg 11, as shown in Fig. 3. It is.

In the example shown in FIG. 3, the shaft of the support 12 is a spherical shell! The upper end of the support and the lower end of the tripod are fixed to the inner surface of the spherical shell to suit any diameter.

In this case as well, the same effects as in the above example can be obtained by having a structure in which each member can be carried in and out through the opening of the spherical shell and assembled and disassembled within the spherical shell.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the schematic structure of one example of a deep-sea submersible research vessel, Fig. 2 is a front view showing an embodiment of the present invention with the spherical shell cut away, and Fig. 3 is a front view showing another embodiment. It is a diagram. l... Spherical shell 2, 12... Support 5...
Arm 6... Cutting tool 7... Opening
9...Control unit 7-

Claims (1)

[Claims] In a device for cutting the inner surface of a spherical shell having an opening in the completed state,
A strut that can be fixed at a position centered on the diameter for any given diameter of the inner surface of the spherical shell, and a strut that can rotate around the strut and move in the axial direction of the strut and in the direction perpendicular to the strut. The above-mentioned apparatus has an arm extending in a radial direction from the support, a sharp cutting tool provided at the tip of the arm, and a control section that controls the rotation and movement of the arm and the cutting movement of the cutting and printing tool. pillar,
A device for cutting the inner surface of a spherical shell, characterized in that the arm portion and the cutting tool have a structure that allows for carrying in and out of the spherical shell through the opening and for assembly and disassembly within the spherical shell.